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Outer Planets Flagship Mission Studies OuterOuterOuter PlanetsPlanetsPlanets FlagshipFlagshipFlagship MissionMissionMission StudiesStudiesStudies Curt Niebur OPF Program Scientist NASA Headquarters Planetary Science Subcommittee June 23, 2008 Overview ¾ NASA is currently mid way through a six month long Phase II study of the remaining two candidate Outer Planet Flagship Missions ¾Europa Jupiter System Mission (EJSM) ¾Titan Saturn System Mission (TSSM) ¾ NASA plans to select a single Outer Planet Flagship mission to be pursued jointly with ESA and other international partners. ¾ The study plan includes a NASA only option in addition to the collaborative options. According to Phase II study ground rules the funding cap is $2.1B FY07 2 Outer Planet Flagship Mission Study Process Submitted 8/07 Downselected 12/07 Titan Saturn System Mission Downselect 11/08 Review 8-11/07 Started 2/08 Titan Saturn System Mission TMC and Phase II or Science Europa Study Europa Jupiter Panel Jupiter System Mission System Mission 3 NASA Phase II Study – Key Milestones • Joint SDT members selected…………………………………….Feb 1, 2008 • Study Kickoff……………………………………………………..Feb 9, 2008 • First Interim Review…………………………………………….April 9, 2008 • ESA Concurrent Design Facility Studies –kickoff…………….May 21, 2008 • Science Instrument Workshop………………………………….June 3-5, 2008 • Second Interim Review………………………………………….June 19-20, 2008 • ESA Concurrence Design Facility Studies – Outbrief…………July 27, 2008 • Phase II Initial Report…………………………………………..Aug 4, 2008 • Science and TMC Panels reviews ……………………………...Sep 9-11, 2008 – Europa Jupiter System Mission (EJSM) – Titan Saturn System Mission (TSSM) • Phase II Final Report……………………………………………Oct 22, 2008 • Decision on mission………………………………………………Nov 2008 4 Second Interim Review – Objectives • Determine the portion of “decadal survey science” at both Europa and Titan that can be accomplished with the “core mission” that best meets the $2.1B FY07 funding cap established in the study ground rules • Determine if there is a “sweet spot” in the trade space between science, cost and risk and estimate the additional cost of reaching this • Estimate the cost to NASA of a mission that achieves “full decadal” science • Characterize the launch opportunities between 2016 and 2022 for missions to Europa and Titan • Assess the interrelationships between the ESA and NASA missions with respect to launch dates 5 JEO Venn Diagram 6 7 JEO Core Mission Slide (LA, IPR, IRS, MAC, WAC, MAPS) 8 JEO Tech Slide 9 JEO Sweet Spot Slide 10 11 TSSM Science Obs Slide 12 TSSM Core Mission Slide 6 instr. (HiRIS, TiPRA, PMS, SMS, TIRS, MAPP) + RSA 13 TSSM ESA In Situ Slide 14 TSSM Sweet Spot Slide 15 16 Comparison of Europa & Titan Options Mission Europa Jupiter System Mission Titan Saturn System Mission NASA Jupiter Europa Orbiter NASA only Atlas 541, 5 MMRTGs Atlas 541, 5 MMRTGs 6 instruments plus Radio Science(O) 6 instruments plus Radio Science Core Atlas 551, 5 MMRTGs 6 instruments plus Radio Science(O) ESA Lander (300 kg available, 150 kg allocation) Sweet Spot Atlas 551; 5 MMRTGs SEP or Two launch; 5 MMRTGs 10 instruments plus Radio Science (Atlas 551 w SEP, A401 for 2nd LV) More diverse tour 6 instruments plus Radio Science(O) ESA Lander plus ESA Montgolfiere (>600 kg allocation) Decadal / Delta IVH; 6 MMRTGs Same launch as above Enhanced 13 instruments plus Radio Science 6 instruments plus Radio Science(O) 2.5 more months in Europa orbit 18 additional months in Titan orbit penetrator demonstration ESA Lander plus ESA Montgolfiere (>600 kg allocation) 17 Cost summaries for Europa and Titan options Europa Jupiter System Mission Titan Saturn System Mission FY07 $B RY $B FY07 $B RY $B NASA Only 2.1 2.7 2.1 2.6 Core 2.2 2.8 Sweet Spot 2.5 3.0 2.3 3.0 Full Decadal 3.1 3.8 2.4 3.2 These costs are still under review and will be refined in the final study report 18 The Road Ahead • Clear to HQ management that the added science of these missions was clearly worth the (relatively) small additional investments over the imposed $2.1B cap – Directed to refocus study effort on “Sweet Spot” missions with launch regime of 2018-2022 – Replan study schedule and budget • Continue community involvement and Instrument Workshops – OPAG meeting (Nov. 6-7) – Instrument Workshops (June 3-5, TBD) –OPFM website at http://opfm.jpl.nasa.gov/ • Keep in mind that OPF is a complex international mission that is currently in pre-phase A – We should expect some changes as we move toward and through Phase A (programmatics, schedules, unforeseen technical issues) – But the important things will not change (Europa radiation environment, Titan surface conditions, key science objectives) 19 Backup Slides 2007 Study Review Results Study Form A: Form B: Science Form C: Mission Science Implementation Risk Implementation Risk Merit Enceladus G/F Not Voted Not Voted Titan Explorer E/VG Medium High Europa Explorer E/VG Medium High (2015) Europa Explorer E/VG Medium Medium (2017) Jupiter System VG/G High High Observer 21 Science Panel Significant Findings from 2007 Study (1) Enceladus Science Merit: Good/Fair – Enceladus is an obvious and tempting target – The desirability of a lander to do chemical analyses is demonstrated – The polar orbits used by the Enceladus Orbiter contain the high priority science but are too short, too few, and too late – For the Saturn Orbiter with Lander concept, too much of the anticipated science yield depends on Enceladus flybys – The report does not adequately address the multiple competing hypothesis for plume origin, so the mission's potential biological significance is compromised Titan Explorer Science Merit: Excellent/Very Good – Science return from the baseline mission (orbiter plus lander plus balloon) will be extremely rich – The descope from baseline mission (orbiter plus lander plus balloon) to orbiter plus lander still provides a viable flagship mission with compelling science – The orbiter-only mission addresses the first of two major objectives (to explore Titan as an evolving Earthlike system) of the mission very well. – An orbiter only-mission severely compromises the second of two major objectives (to explore Titan’s organic inventory) for the mission 22 Science Panel Significant Findings from 2007 Study (2) Europa Explorer Science Merit: Excellent/Very Good – Science objectives are comprehensive, compelling, and mature – The geological and geophysical objectives, investigations, and proposed measurements in particular are comprehensive – Jovian tour offers important advance in comparative planetology – The Europa Explorer mission provides a clear descope pathway from a comprehensive baseline mission, through staged steps, to a floor mission that still meets all “priority 1” science objectives – The chemistry objective, including portion related to habitability, was not comprehensively addressed Jupiter System Observer (JSO) Science Merit: Very Good/Good – JSO offers a unique opportunity to study all four Jovian satellites – The mission design provides comprehensive geophysical and geological interrogation of Ganymede – Nearly continuous monitoring of Ionian volcanism for 3 years or more – JSO will acquire extensive global visible and IR and stereo topographic mapping data of the other Galilean satellites – Synoptic Jupiter atmosphere measurements will be obtained with greatly improved spatial resolution and potential spatial and temporal coverage – The Jupiter atmospheric scientific investigations in particular were poorly justified – The science theme of Habitability, which is called out in the Roadmap and is important to astrobiology, was not considered in formulating the science plan – The SDT did not address how the mission and expected results can be used to study solar system formation and the chemical evolution of the proto-stellar disk 23 TMC Panel Significant Findings from 2007 Study (1) Enceladus Science Implementation: Not Voted; Mission Implementation: Not Voted – Immature mission architecture – None of the design concepts presented appear feasible – Mission lifetimes too long to be considered an acceptable risk – Mass margins are inadequate. – Feasibility of landing on Enceladus could not be assessed – Lack of definition in the requirements for the site selection, the landing event and the characterization of the landed operating environment and impacts on the Lander Design. Titan Explorer Science Implementation: Medium; Mission Implementation: High – Extremely challenging design concept in terms of complexity, mass and cost – Aerocapture for the baseline architecture drives substantial design risk for the Orbiter – Lander and Aerial Vehicle entry systems and the Orbiter aeroshell are new designs – Instrument concepts may not meet a number of the required science objectives – Considerable uncertainty and immaturity associated with the design and implementation of the Chemical analysis Instrument operating in the Titan environment. 24 TMC Panel Significant Findings from 2007 Study (2) Europa Explorer 2015: Science Implementation: Medium; Mission Implementation: High 2017: Science Implementation: Medium; Mission Implementation: Med – 2015 launch of EE is not credible, considering the time required to resolve radiation issues prior to the release of instrument AO’s and funding availability – Detailed science traceability matrix that identifies goals and objectives, offers methods for the investigation and details measurement requirements – Radiation-induced effects on the measurement quality is a significant issue – The flight system instrument accommodation concept is detailed – The 2017
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